Surveying-rod.



PATENTBD JULY 24, 19.06,;

` Hl Gc SURVEYING ROD. APPLIU'ATION FILED 110112.19114.

4 luik HERBERT G. CLARK, OF HARTFORD, CONNECTICUT.

SURVEYING-ROD.

Specification of Letters Patent.

Patented July 24, 1906.

Application filed November Z, 1904. Serial No. 231,101.

To @ZZ whom, t may concern Be it known that I, HERBERT G. CLARK, acitizen of the United States, and a resident of Hartford, in the county of Hartford and State of Connecticut, have invented a certain new and Improved Surveying-Rod, of which the following is a specification.

The invention relates to surveyors or linemens rods, commonly so called, and more particularly to a rod for long-distance and accurate Work. f

The object of the invention is to provide a rod which will give the greatest accuracy in the readings, both for long and short distance work, and one in which the sight-line will always be maintained concentric with the rest-point of the rod.

A further object is to provide an adjustable sight-line for the rod, and a still further object is to provide a rest-point which may be made interchangeable and used on either side of the rod.

Another object of the invention is to provide with the above features a leveling attachment for plumbing the rod and to arrange this leveling attachment so that it may be adjusted to compensate for variations.

Figure 1 is a front face view of the improved rod.. Fig. 2 is a detail view, on enlarged scale, of the several parts of the rod, partially broken in section to better show the construction. Fig. 3 is a detail face view of the plumb-level and restpoint section, this view showing a rest-point without stop-collar. Fig. 4 is a sectional view through the upper end of the rod.

In the accompanying drawings the letter c denotes the rod as a whole, which, as shown herein, is of substantially rectangular form as to cross-section and is provided on one face with markings, preferably of various colors. At the center of the face of the rod is formed an opening or groove o of substantial width and depth, and along this groove is stretched the sight-line. At the lower end of the rod its opposite edges are beveled, as at c, and fitting and inclosing the beveled end is a shoe d, preferably formed of metal and provided on opposite sides with bosses e c". These bosses are bored to receive the rest-point f, which is preferably formed of hardened steel and is provided with a shoulder f to prevent its being driven through the opening in the casting, but permitting it to be withdrawn from the bottom of the rod. To secure this rest-point in various positions, a set-screw gis passed through the boss to engage and hold the rest-point'. i

In addition to the support afforded by the boss and set-screw the surface of the rod is recessed, as at h, and across this recess and adjustably secured with reference thereto is a guide-strap h. 4 The necessary means for securing a transverse adjustment of the strap is provided by the slotted openings i and locking-screws i. As shown in the drawings, there is a guide-strap on either side of the rod, and the shoe-piece has bosses on both sides, so that the rod may be constructed as a double-face rod, if desired. This latter adjustment forms a convenient means for plumbing the rest-point with reference to the rod and may be used for correcting inaccuracies due to warping and like causes.

The rest-point f is of considerable length and at its upper end has two openings bored at right angles to each other, that in the eX- treme end of the rest-point being at the center of the cylindrical bar from which the point is made.

The sight-line, which is preferably of a flexible material, as cord or Wire, is passed through this end opening and secured, as by knotting the end of the cord or wire, after passing it out through the transverse opening. Obviously this brings the sight-line directly over and coincident with the center of the point.

The sight-line k lies in the groove b and at its upper end is secured to an adjustable member or turnbuckle l, one end of which is secured to a bracket -piece l', passing over the upper end of the rod and forming a shoe therefor. The turnbuckle may be used for tensioning the sight-line and adjusting it to various lengths.

One feature of the adjustable rest-point and sight-line resides in the ability to withdraw the rest-point from the end of the rod. This permits lengthening the rest-point at a sufiicient distance to insert it below ordinary levels and in inaccessible places, and it is to be noted that the sight-line k is exactly coincident in position with the axis of the rest-point, and therefore the line of sight must always be in the plane of the point upon which the rod rests, provided, of course, the rod is properly plumb.

In work requiring the greatest accuracy it is found that better results can be obtained by having the sight-line arranged as indicated herein, inasmuch as the line is abso lutely coincident with the point which is IOC) placed upon any given mark. The turning ofthe rod will thus not affect the accuracy ol' the operator in setting his instrument With the greatest degree of accuracy. In ordinary rods Where there is simply a line drawn upon the face of a rod and not directly coincident with the center oi the rest-point improper readings are liable to be secured.

Extending across the back of the rod is a bracket m, having an upturned 'flange m, Which serves as a guard for a plumb-level n. This level is mounted on-the bracket between the flange and the Aface of the rod and is provided at yeither end with adjusting-screws 0 and a lock-nut 0 for varying the position of the level and properly adjusting it.

Obviously various changes as to details might be made Without materially altering the scope or intent of the invention, which contemplates, among other things, the arrangement of a sight-line which Will always be in the plane of the center of the rest-point.

l/Vhat I claim as my invention, and desire to secure by Letters Patent, is-

l. A linemans rod including a rod having a rest-point secured in one end, a flexible sight-line extending from said rest point along the rod and arranged coincident with the central axis of' said rest-point.

2. A linemans rod provided With an adjustable rest-point secured in one end and having a flexible sight-line attached to and extending therefrom and coincident with the plane ofthe central axis of said rest-point.

3. In a device of the class specified, a rod,

, a rest-point removably attached to one end l thereof, and a flexible sight-line secured to and extending from the center of said restpoint and arranged in the plane of the center of said point.

4. In a device of the class specified, a rod or bar, a shoe fitting one end thereof and provided With sockets, a rest-point adjustably arranged in said sockets, and a sight-line extending from said rest-point along the bar and arranged in the plane of the central axis of said rest-point.

5. In a device of the class specified, a rod, a rest-point arranged at one end thereof, a Iiexible sight-line extending from said restpoint, and adjustable means for securing the opposite end of the said sight-line to the rod.

6. In a device of the class specied, in combination, a rod provided at one end with a rest-point, having a groove extending along said rod, a sight-line arranged coincident with the plane of the center of the rest-point and extending along said groove to the opposite end of the rod, and means for securing the sight-line at said opposite end.

` 7. In combination in a device of the class specilied, a rod, a rest-point adjustably arranged at one end thereof, a flexible sightline attached to and extending from said restpoint along the rod and lying coincident With the central axis of the rest-point and an adjustable plumbing-level arranged transversely to the sight-line.

HERBERT G. CLARK. Witnesses:

CLARA E. Jor-rNsoN, L. E. BERxoviToH. 

